Dreams are one-sixtieth of prophecy, and also “they speak falsehood” — and both are true; sometimes yes and sometimes no. And it says in the Talmud when yes and when no.
I didn’t understand why this is a question for a psychologist?

Because when I deal with facts, I don’t make do with quotations from the Talmud; I look for factual confirmation. I’m not familiar with any, but this is a question for a psychologist (whether dreams come true in any statistically significant way). The Talmud does not say when yes and when no, but the commentators dealt with this. See my article in Midah Tovah on the portion of Miketz, 2007: https://docs.google.com/document/d/0BwJAdMjYRm7IT0h1VzVSNlBoMkk/edit?resourcekey=0-m0NOdxoip2YMbKYUodVydA

The Talmud writes, for example, that one who sees a snake in a dream should anticipate etc., in tractate Berakhot.
And throughout the Hebrew Bible (Tanakh) we find dreams that came true.